<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<form name="form1" id="form1">
			用户名:			
		</form>
		<form id="form2">
			选择年份<select id="sel1"></select>
		</form>
		<button onclick="add()">添加</button>
		<script>
			function add()
			{
				var txt = document.createElement("input")
				txt.type="text";
				txt.name="username"
				form1.appendChild(txt);
			}
			var op1 = document.createElement("option");
			var op1txt = document.createTextNode("2024");
			op1.appendChild(op1txt);
			sel1.appendChild(op1);
		</script>
	</body>
</html>